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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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package org.graalvm.compiler.truffle.runtime;

import static com.oracle.truffle.api.CompilerAsserts.partialEvaluationConstant;
import static com.oracle.truffle.api.CompilerDirectives.inCompiledCode;
import static org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.castArrayFixedLength;
import static org.graalvm.compiler.truffle.runtime.OptimizedCallTarget.unsafeCast;

import com.oracle.truffle.api.CompilerDirectives;
import com.oracle.truffle.api.impl.AbstractFastThreadLocal;

public abstract class GraalFastThreadLocal extends AbstractFastThreadLocal {

    protected GraalFastThreadLocal() {
    }

    @Override
    public abstract void set(Object[] data);

    @Override
    public abstract Object[] get();

    @Override
    @SuppressWarnings("unchecked")
    public final <C> C fastGet(int index, Class<C> castType, boolean invalidateOnNull) {
        Object[] data;
        if (inCompiledCode()) {
            partialEvaluationConstant(index);
            partialEvaluationConstant(castType);
            Object[] array = get();
            if (array == null) {
                if (invalidateOnNull) {
                    CompilerDirectives.transferToInterpreterAndInvalidate();
                }
                return null;
            }
            Object v = castArrayFixedLength(array, index + 1)[index];
            C result = unsafeCast(v, castType, true, false, true);
            return result;
        } else {
            data = get();
            if (data == null) {
                return null;
            }
            C result = (C) data[index];
            assert castType == null || result == null || result.getClass() == castType : "Invalid exact type returned";
            return result;
        }
    }

}
